A Learning System and Its Psychological Implications

Abstract

ACT Is a computer simulation prooram IMI useos a propositional neolwork to rflptesenl knowledge of facta and a aet of productiona (condition - action rules) to rl'prcsl'nl knowlt'dge of procl'dlxt~s. Thl're are currently four different mechanisms by which ACT can make additions and modifications to its stol of product i on~: dl'$ignalion, strengthening, gtont~ralization, and discrimination. Designation refers to the ability of productions to call for thl' crl'ation of neow productions . Strengthening a production involves adjusting the amount of system reaources that will be allocated to its proct'ssing. Finally, gc.-noralizalion and discrimination refer to complementary processes that produce better performance by either extl'nding or restr icting the rangto of situations in which a production will apply. These learning mechanl- are used to simulate experiment• on prototype formation. ACT succeosslully accountt lor the effecla of dlatance of instances from a central tendency, freqt,.ncy of individual instances, and the family resemblance~ structure of categor i es.